During a study a bottlenose dolphin was blindfolded and instructed to mimic the actions of a trainer. When he wasn’t able to use sight, the dolphin switched to another technique: emit sounds, listen to the echo and interpret the resulting sound waves. Read more …

A video from the BBC’s 2003 Wildlife on One special Dolphins: Deep Thinkers? with David Attenborough about dolphins amazing abilities to sonar. It shows that a dolphin is able to match an object that it is hidden from its vision, with one that it sees.